Florida’s Everglades, which once covered the lower half of that large state, is the home to alligators, poisonous snakes and mosquito clouds thick enough to darken the sun.

That’s not why we humans have spent a good part of the last 200 years trying to destroy it.

Nah, we’ve tried to drain and pave over the Everglades for the most human of all reasons: greed.

PBS’s American Experience series tracks the progress of our efforts in a fascinating two-hour documentary called The Swamp, which airs Tuesday at 9 p.m. ET (check local listings).

It’s a frustrating story, though not without periodic rays of hope. The most important question it raises may be the one we’re answering on the fly: Will we, at some point, understand the cost of what we do to this large parcel of nature?

America’s largest wetland, the Everglades was considered no man’s land back when the United States was founded.

It was inhospitable at best and generally seen as downright useless. All that water made it too wet to farm, and its tangle of vegetation combined with its lethal population of living critters discouraged almost everyone from even trying to settle there.

Then, late in the 19th century, Northern rich guy Hamilton Disston bought four million acres from the state – for a million dollars, which finally wiped out the last of Florida’s Civil War debt – and announced he was going to drain them.

Once he had, they would be available for industry, homesteading and most of all farming. After all, there was plenty of moisture, and the warmer climate meant you could grow crops almost year-round.

Disston failed, on pretty much all counts, but he laid down the template. State officials, including Gov. Napoleon Bonaparte Broward, eventually dusted off all his promises. So did a land huckster named Richard Bolles, whose scams helped precipitate the Florida real estate crash of the 1920s.

Those who saw the Everglades as an opportunity rather than an ecosystem didn’t give up, and after the Army Corps of Engineers went to work in the wake of World War II, the Everglades had been reduced to half its original size.

Along the way, there were other significant dramas, like the way black individuals and workers were exploited and ultimately considered expendable. But the major battle was always environmental.

Early on, the Disstons and others paid no attention to the impact from re-engineering nature. For instance, it wasn’t until the water in Miami started tasting salty that a new crop of engineers realized this inconvenient truth: With so much less fresh water now coming from the Everglades, the salt water from the ocean was pushing inland to Miami’s water supply.

The impact on the Everglades flora and fauna, needless to say, was even more dramatic, and not in a good way.

It took Marjory Stoneman Douglas’s 1947 book The Everglades to start reminding people what we would lose if we ever succeeded in replacing all those sawgrass marshes with suburban lawns or citrus groves.

While nominally protected today, the surviving Everglades remains under threat, because there’s always someone or some institution that sees money to be made from developing scruffy, muddy land that’s otherwise just sitting there.

Over the long haul, meaning the next tens of millions of years, nature will win. The question is whether we humans can secure shorter-term victories without wrecking everything for both the ‘Glades and us.

The Swamp is based on the book of the same name by Michael Grunwald, who also appears here as an expert commentator. It was directed and produced by Randall MacLowry, with Mark Samels as executive producer. High marks to everyone involved.